Fox squirrels are barely documented in Arizona, with just 16 records in state occurrence databases, the thinnest showing of any of the state’s tree squirrels. That scarcity fits the species’ own biography: fox squirrels are native to the eastern and central United States, and every Arizona sighting sits at the far edge of a range people extended west through river corridors and planted trees.
A trail that follows the Colorado River
Ten of the state’s 16 records cluster around Yuma and the lower Colorado River, with a scattering of single sightings elsewhere. Fox squirrels need river bottoms, mature shade trees, and open ground beneath them, habitat the lower Colorado’s irrigated groves and riverside plantings supply and the open Sonoran Desert and high pine forest elsewhere in the state don’t.
Not one of Arizona’s native tree squirrels
Arizona already carries two genuinely native tree squirrels, the gray-bodied Arizona gray squirrel and the tufted-eared Abert’s squirrel of the ponderosa belt. A fox squirrel reads differently from both: it’s noticeably larger and heavier, with a rusty orange to tawny wash across the belly and tail that neither of Arizona’s native squirrels shows.
Status in Arizona
Fox squirrels aren’t flagged as nonindigenous in Arizona by USGS NAS, so the state’s own record treats the handful of sightings as native to their mapped range here. Given how thinly and narrowly those records cluster around the lower Colorado River corridor, that’s a foothold living at the extreme edge of a range shaped as much by river-bottom plantings as by the species’ original eastern and central range.
